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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands using echo from sorted by
Terminal - Commands using echo - 1,331 results
{ u="http://twitter.com/commandlinefu"; echo "Subject: $u"; echo "Mime-Version: 1.0"; echo -e "Content-Type: text/html; charset=utf-8\n\n"; curl $u ; } | sendmail recipient@example.com
2010-02-24 04:18:30
User: pascalv
Functions: echo sendmail

This will send the web page at $u to recipient@example.com . To send the web page to oneself, recipient@example.com can be replaced by $(whoami) .

The "charset" is UTF-8 here, but any alternative charset of your choice would work.

`wget -O - -o /dev/null $u` may be considered instead of `curl $u` .

On some systems the complete path to sendmail may be necessary, for instance /sys/pkg/libexec/sendmail/sendmail for some NetBSD.

echo "Starting Daemon"; ( while :; do sleep 15; echo "I am still running =]"; done ) & disown -h $!
2010-02-23 19:17:05
User: daleki
Functions: echo sleep

You don't want the -ar parameters in this case. The man page for BASH_BUILTINS(1) states:

"-a option means to remove or mark all jobs" and

"-r option without a jobspec argument restricts operation to running jobs"

In this case we are supplying the process id of the job to disown so neither of these should be used.

echo 0 >/selinux/enforce
2010-02-17 16:33:26
User: svnlabs
Functions: echo

just change SELINUX=enforcing to SELINUX=permissive, and you're done. Reboot if you want to prove it.

spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://www.google.com/tbproxy/spell|sed -n '/s="[0-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}'|tee >(grep -Eq '.*'||echo -e "OK");}
2010-02-17 08:20:48
User: eightmillion
Functions: echo grep sed tee

I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this:

spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}';}
for domain in `cat list_of_domains.txt`; do echo $domain; whois $domain >> output.txt; done
2010-02-15 17:13:45
User: pathcl
Functions: echo whois

Outputs multiple whois from a plain text file.

for i in `ndd /dev/ip \? | awk '{ print $1 }' | egrep -v "ip6|status|icmp|igmp|\?"` ; do echo $i `ndd -get /dev/ip $i` ; done | grep -v \?
2010-02-15 12:32:33
User: felix001
Functions: awk echo egrep grep

This command is jsut for the main IP settings of ndd. if you need ip6 or icmp edit the text within the egrep inclusion area.

Felix001 - www.Fir3net.com

uri_escape(){ echo -E "$@" | sed 's/\\/\\\\/g;s/./&\n/g' | while read -r i; do echo $i | grep -q '[a-zA-Z0-9/.:?&=]' && echo -n "$i" || printf %%%x \'"$i" done }
2010-02-13 01:39:51
User: infinull
Functions: echo grep printf read sed

This one uses hex conversion to do the converting and is in shell/sed only (should probably still use the python/perl version).

echo "$url" | perl -MURI::Escape -ne 'chomp;print uri_escape($_),"\n"'
2010-02-13 00:44:48
User: eightmillion
Functions: echo perl
Tags: perl

Converts reserved characters in a URI to their percent encoded counterparts.

Alternate python version:

echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'
echo "$@" | sed 's/ /%20/g;s/!/%21/g;s/"/%22/g;s/#/%23/g;s/\$/%24/g;s/\&/%26/g;s/'\''/%27/g;s/(/%28/g;s/)/%29/g;s/:/%3A/g'
echo $(cat file)
smenu() ( IFS=',' ; select x in $*; do echo "$x" | xsel -i; done )
2010-02-08 15:33:53
User: bartonski
Functions: echo
Tags: xsel select

The function will take a comma separated list of items to be 'selected' by xsel -i:

smenu "First item to paste,Paste me #2,Third menu item"

You will then be prompted to choose one of the menu items. After you choose, you will be able to paste the string by clicking the middle mouse button.

The menu will keep prompting you to choose menu items until you break out with Control-C.

echo "I'm going to paste this into WINDERS XP" | xsel -i
2010-02-08 00:23:43
User: bartonski
Functions: echo
Tags: X xsel putty XMing

Set up X forwarding in PuTTY, with X display location set to :0.0

Launch PuTTY ssh session.

Launch Xming. Make sure that display is set to :0.0 (this is default).

echo "I'm going to paste this into WINDERS XP" | xsel -i

will insert the string into the windows cut and paste buffer.

Thanks to Dennis Williamson at stackoverflow.com for sharing...

echo "There are $(($(date +%j -d"Dec 31, $(date +%Y)")-$(date +%j))) left in year $(date +%Y)."
/bin/bash echo -n "Let's POST MORE, PLEASE!"
2010-02-05 18:52:45
User: editorreilly
Functions: echo

I absolutely love this website, and appreciate every contribution. This is the first place I go when I'm stuck, you all have some great ideas. But contributions seem to be slipping a little. If all of us could contribute more code from time to time, this site would be absolutely incredible. Since I'm a relative newcomer to commandline-fu, I don't have the knowledge to contribute much, but I will do what I can.

newest () { DIR=${1:-'.'}; CANDIDATE=`find $DIR -type f|head -n1`; while [[ ! -z $CANDIDATE ]]; do BEST=$CANDIDATE; CANDIDATE=`find $DIR -newer "$BEST" -type f|head -n1`; done; echo "$BEST"; }
2010-02-04 12:40:44
User: shadycraig
Functions: echo head

Works recusivley in the specified dir or '.' if none given.

Repeatedly calls 'find' to find a newer file, when no newer files exist you have the newest.

In this case 'newest' means most recently modified. To find the most recently created change -newer to -cnewer.

echo '.dump' | sqlite3 your_sqlite.db > your_sqlite_text.txt
2010-02-04 07:58:41
User: alamati
Functions: echo

If you want edit your sqlite database in any uft8 supported editor, you can dump whole sqlite database to plain text.

echo {1..199}" bottles of beer on the wall, cold bottle of beer, take one down, pass it around, one less bottle of beer on the wall,, " | espeak -v english -s 140
2010-02-04 04:38:52
User: op4
Functions: echo

you know the song... sing along

echo "DISPLAY=$DISPLAY xmessage setup suphp perms htscanner acct#101101 host2.domain.com" | at 23:00 Feb 8
2010-02-04 04:26:24
User: op4
Functions: at echo

setup for reminder in 5 days, added the date in the future. To run a job at 4pm three days from now, you would do at 4pm + 3 days, to run a job at 10:00am on July 31, you would do at 10am Jul 31 and to run a job at 1am tomorrow, you would do at 1am tomorrow.

echo "DISPLAY=$DISPLAY xmessage convert db to innodb" | at 00:00
while read l; do echo $RANDOM "$l"; done | sort -n | cut -d " " -f 2-
2010-02-03 22:36:34
User: ketil
Functions: cut echo read sort

If you need to randomize the lines in a file, but have an old sort commands that doesn't support the -R option, this could be helpful. It's easy enough to remember so that you can create it as a script and use that.

It ain't real fast. It ain't safe. It ain't super random. Do not use it on untrusted data. It requires bash for the $RANDOM variable to work.

echo 'c84fa6b830e38ee8a551df61172d53d7 myfile' | md5sum -c
ruler() { for s in '....^....|' '1234567890'; do w=${#s}; str=''; for (( i=1; i<=(COLUMNS + w) / $w; i=i+1 )); do str+=$s; done; str=${str:0:COLUMNS} ; echo $str; done; }
2010-01-31 05:55:00
User: dennisw
Functions: echo

A similar version for Bash that doesn't require cut and shortens the function in a few places. And it uses local variables. (similar to a version by eightmillion in a comment on the another version)

echo alias xkcd="gwenview `w3m -dump http://xkcd.com/|grep png | awk '{print $5}'` 2> /dev/null" >> .bashrc
2010-01-30 20:38:16
User: GinoMan2440
Functions: alias echo

Add an alias to your .bashrc that allows you to issue the command xkcd to view (with gwenview) the newest xkcd comic... I know there are thousands of them out there but this one is at least replete with installer and also uses a more concise syntax... plus, gwenview shows you the downloading progress as it downloads the comic and gives you a more full featured viewing experience.

[ "c84fa6b830e38ee8a551df61172d53d7" = "$(md5sum myfile | cut -d' ' -f1)" ] && echo OK || echo FAIL
md5 myfile | awk '{print $4}' | diff <(echo "c84fa6b830e38ee8a551df61172d53d7") -
2010-01-29 16:57:13
User: voidpointer
Functions: awk diff echo

Makes sure the contents of "myfile" are the same contents that the author intended given the author's md5 hash of that file ("c84fa6b830e38ee8a551df61172d53d7").